Indole derivatives having specific useful activities are well known. For instance, in French patent FR 2260332 certain 3-substituted derivatives of 1-phenyl-2-aminocarbonylindole having pharmaceutical activity are described. In German patent application DE 2008692 certain 3-aminocarbonylindole derivatives having herbicidal and pharmaceutical activity are described. From Japanese patent applications J5 0070357 and J5 0070358 1,3-disubstituted 2-aminoacetylindole derivatives and 1,3-disubstituted 2-(3-amino-propionyl)indole derivatives are known. These derivatives have antifungal as well as pharmaceutical activity. Additionally, DE 1966206 discloses 5-chloro-1-(2-flurophenyl)-3-methyl-1H-indole-2-carboxamide as an intermediate in the preparation of certain 1,4-benzodiazepines which are useful as pharmaceuticals. There is no indication that this compound has any fungicidal activity.
It has now been found that certain new indole derivatives, especially indole derivatives which are unsubstituted at the 3-position, show excellent fungicidal activity, particularly against Phytophthora infestans and Plasmopora viticola.